1. Field of the Invention
The invention relates to heat shrink packaging machines and more particularly to machines for packaging circular articles such as tape rolls with inert or non-adhesive heat-shrinkable film in a manner which permits the articles to be easily separated.
2. Description of the Prior Art
When objects such as stacked tape rolls are packaged, it has been necessary to place separators such as thin paper sheets between the rolls in order to prevent them from sticking together and to facilitate separation. Recently, a form of heat shrink package for articles such as stacked tape rolls has been developed. The articles are coaxially aligned in horizontally spaced relation with each other and a heat-shrinkable film is placed around them. If a self-adhering film is used, the wrap can be drawn tightly around the rolls at the wrapping station with the film ends being overlapped. This will hold the rolls in position while they are conveyed to the heat shrink oven. The oven causes the film between the articles to shrink. After discharge, the wrapped articles may be compressed, and the shrunk film between the articles will act as separators.
Self-adhering film does not lend itself, however, to overlapping when used to wrap articles such as tape rolls. It has been found that the film often does not hold and the package can come apart. For this reason it is desirable to use inert-heat-shrinkable film which is wrapped around the articles and cut with a hot wire to create a non-overlapping seam. However, this process necessarily leaves some looseness in the package until it reaches the heat shrink oven. This creates the possibility that one or more of the articles may become tipped or skewed during their movement from the wrapping station to the oven, especially if they are narrow and unstable.